問題詳情
17.如圖(八)，圓O分別與△ABC的三邊相切於D、E、F三點，若 
，則 
＝？
(A) 18
(B) 27
(C) 36
(D) 45 。
參考答案
答案：B
難度：計算中-1
書單：沒有書單，新增
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